IR limits, pregalactic stars, neutrino decay and quantum gravity
Astroparticle Physics 11:1-2 (1999) 103-109
Abstract:
The results of recent studies which seek to probe fundamental aspects of astrophysics using TeV gamma-ray observations of active galactic nuclei (AGN) are presented. These analyses take advantage of both spectral and temporal information together with the unique combination of the very high energies and large distance scales involved. The next generation of instruments currently planned are expected to make substantial improvements in the study of such phenomena. © 1999 Elsevier Science B.V. All rights reserved.Limits to quantum gravity effects on energy dependence of the speed of light from observations of tev flares in active galaxies
Physical Review Letters 83:11 (1999) 2108-2111
Abstract:
We have used data from a TeV gamma-ray flare associated with the active galaxy Markarian 421 to place bounds on the possible energy dependence of the speed of light in the context of an effective quantum gravitational energy scale. Recent theoretical work suggests that such an energy scale could be less than the Planck mass and perhaps as low as 10^16 GeV. The limits derived here indicate this energy scale to be in excess of 4×106 GeV for at least one approach to quantum gravity in the context of D-brane string theory. To the best of our knowledge this constitutes the first convincing limit on such phenomena in this energy regime. © 1999 The American Physical Society.Measurement of the multi-TeV gamma-ray flare spectra of Markarian 421 and Markarian 501
ASTROPHYSICAL JOURNAL 511:1 (1999) 149-156
TeV blazars: Status of observations
ASTROPHYS LETT COMM 39:1-6 (1999) 477-484
Abstract:
The close relation between ground-based TeV observations and satellite borne gamma-ray measurements has been important for the understanding of blazars. The observations which involve the TeV component in blazar studies are reviewed.Discovery of gamma-ray emission above 350 GeV from the BL lacertae object 1ES 2344+514
Astrophysical Journal 501:2 PART 1 (1998) 616-623